<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
</head>
<body>
    <script>

        let obj = {
            name:"张三",
            age:20
        }

        setTimeout(() => {
            obj.name = "李四";
        });
        console.log(obj);  // name= 张三



    </script>
</body>
</html>